import os.path
import pygame
from pygame.sprite import Sprite

from alien_invasion.game_stats import GameStats
from alien_invasion.settings import Settings


class Ship(Sprite):

	def __init__(self, ai_settings: Settings, screen: pygame.SurfaceType
				 , custom_size: tuple = (0, 0), image_name="images/ship1.png"):
		"""Initialize the ship and set its starting position."""
		super().__init__()
		self.screen = screen
		self.ai_settings = ai_settings

		# Load the ship image and get its rect.
		fullname = os.path.join('.', image_name)
		try:
			self.image = pygame.image.load(fullname)
		except pygame.error:
			print('Cannot load image: ', image_name)
			raise SystemExit
		if custom_size == (0, 0):
			custom_size = ai_settings.ship_size
		self.image = pygame.transform.scale(self.image, custom_size)

		self.rect = self.image.get_rect()
		self.screen_rect = screen.get_rect()

		# Start each new ship at the bottom center of the screen.
		self.rect.centerx = self.screen_rect.centerx
		self.rect.bottom = self.screen_rect.bottom

		# Store a float value for the ship's center.
		self.center = float(self.rect.centerx)

		# Movement Flags.
		self.moving_right = False
		self.moving_left = False

	def blitme(self):
		"""Draw the ship at its current location."""
		self.screen.blit(self.image, self.rect)

	def update(self, stats: GameStats):
		"""Update the ship's position based on the movement flag."""
		if self.moving_right and self.rect.right < self.screen_rect.right:
			self.center += self.ai_settings.ship_speed_factor * stats.time_passed
		if self.moving_left and self.rect.left > 0:
			self.center -= self.ai_settings.ship_speed_factor * stats.time_passed

		# Update rect object from self.center
		self.rect.centerx = self.center

	def center_ship(self):
		"""Position the ship at center on screen."""
		self.center = float(self.screen_rect.centerx)
